Caveat emptor fixes

[aravol]

"Let the buyer beware" - Given the namability of stones, there exists at least some potential for abuse in the ability for a player to name a stone, only to have it lead somewhere else, potentially somewhere disastrously dangerous. This could be fixed in one of several ways

• Create a new, noncraftable grade of Recall Stone, such that they can only be made and linked by Admins - thus, they can (almost) always be trusted
• Allow for stones which are keyed to a chunk, instead of specific coordinates, perhaps randomly selecting a spot based on openness to the sky, or teleporting to y-256 and granting enough featherfall to survive the results. This reduces the possibility of abuse and makes for more interesting "waypoints" and reception areas (and some hilarity if people must fall from the sky)
• Allow for an "only admins can link" rule. This means while Admins are in charge of setting up the inital waypoints, the ability to copy stones (see feature request Add "Copy Stone" recipie #2 ) allows for players to make more from these initial presets

[Vanhal]

The position is mentioned on the stones though...

[aravol]

Position is mentioned, which might arouse some suspicion, but few will think to memorize positions of various locations - especially if they have a stone to do that for them!

Perhaps the easiest implementation to add an extra NBT tag like "Admin certified" or such, if the stone was Marked by someone Opped on a server? Also slightly more useful than a username, I think, since the list of Ops may not be well-known